Balloon-Occluded Retrograde Transvenous Obliteration (BRTO)

As explained above BRTO is considered principally for gastric varices. There are some sub-categories:

• Active, recent, recurrent or high-risk gastric variceal bleeding, particularly isolated varices, with a usable gastrorenal or gastrocaval shunt.
• Large, high-risk gastric varices — these are very fragile and prone to rupture, bursting, and causing internal bleeding. Vomiting with blood, black stools or tar-like stools are typical manifestations of this. Usually, other treatments are first employed, but if the bleeding returns and the risk of complications is high, BRTO is considered.
• Recurrent hepatic encephalopathy — due to larger shunt, the amount of toxin-rich bypassing the liver increases. This can manifest as confusion, sleepiness, or altered behaviour. In specific cases, BRTO can help.

 

Patient selection for BRTO depends on CT/MR vascular mapping, liver reserve, portal and splenic vein patency, presence of ascites, anatomy of drainage shunt, endoscopy findings, and the patient’s bleeding/encephalopathy history. In some cases, it could be counterproductive — closing the shunt can worsen fluid in the abdomen or enlarge esophageal varices. Typically a liver specialist, gastroenterologist and interventional radiologist decide based on scan findings, overall health and liver function.

BRTO is usually not decided on the basis of a few physical symptoms alone, rather after tests — in particular a CT and endoscopy — show large gastral varices, with a suitable drainage vein. However, some symptoms merit immediate medical evaluation, as these could indicate variceal bleeding:

• Vomiting fresh red blood or dark coffee-grounds like material
• Black tar-like sticky stools
• Maroon or blood-stained stools
• Sudden dizziness, fainting, extreme weakness, low BP, disorientation, fast heartbeat or paleness
• Any new onset of severe fatigue or breathlessness, which may reflect anemia

 

A secondary symptom pattern involves those that come from recurrent hepatic encephalopathy — repeated confusion, memory loss, poor concentration, unusual sleepiness, personality or behaviour changes, disorientation, blackouts, and reduced alertness. A person may have no symptoms at all, before a gastric varix bleeds; large varices are found on routine surveillance checkups, and often these lead to planned treatment.

In such an anatomy-specific intervention, pre-procedural planning is crucial. A contrast CT is the most important modality of imaging to map the gastric varices, gastrorenal shunt, collateral veins, portal vein, splenic vein and ascites. Alongside this, blood counts, liver function, renal function, coagulation profile (clotting ability and factors) and blood counts are essential.

 

Once the patient is cleared for BRTO, local anesthesia is administered and via imaging guidance, an interventional radiologist usually enters through the femoral vein (in the groin); in very specific cases, jugular access may be used, but this is a bit more delicate.

 

The next stage is reaching the shunt. A catheter is advanced through the inferior vena cava and left renal vein into the gastrorenal shunt. In simple terms, a gastrorenal shunt is an abnormally enlarged venous pathway that forms between veins in the stomach and the left renal vein, which normally carries blood away from the kidney.

 

The next step is the actual balloon occlusion. A balloon is inflated in this shunt, and contrast dye helps identify that the varices fill and to identify collateral escape routes. These ‘escape’ channels need to be monitored — if contrast dye accidentally runs into any of these, the outflows may be blocked with coils or agents, so the main treatment agent remains within the varices.

 

After this, comes the obliteration of the varices. A sclerosant (sealing agent) is injected while the outflow is occluded. Essentially, it intentionally damages the variceal lining, while promoting thrombosis. Sclerosants aren’t standardized, globally. The specific agent largely varies based on availability, the experience of the interventional radiology team, approvals, kidney function, bleeding urgency etc. In India, Sodium Tetradecyl Sulfate (SDS) foam is most widely used. In Japan, and parts of East Asia, Ethanolamine Oleate (EO) with contrast is the most common. Polidocanol is also used more selectively in Japan, South Korea and parts of Europe. N-Butyl cyanoacrylate (NBCA) is used as part of a modified version of BRTO.

 

 

Once this step is complete, in conventional BRTO, the balloon may remain inflated for several hours or overnight. Imaging confirms thrombosis of the varices, before the catheter is removed. Post-op surveillance is done via a CT — within 24 hours or several days, depending on the case. Follow up endoscope and imaging assess gastric-varix eradication and look for worsening esophageal varices or ascites (abnormal build up of fluid in the abdomen).

RTO has now become an umbrella term for different types of approaches. Advances in RTO aim to make treatment faster and avoid prolonged balloon use. In traditional BRTO, the balloon needs to remain in place for several hours, and in rare cases it can rupture or shift.

 

PARTO (Plug-Assisted Retrograde Transvenous Obliteration) uses a small vascular plug to block the drainage vein. CARTO (Coil-Assisted Retrograde Transvenous Obliteration) uses tiny metal coils for the same purpose. Once the outflow is sealed, doctors fill the varices with a closing material (usually gelatin foam or a sclerosant). These approaches reduce the risk of balloon rupture. However, they come with some anatomy requirements. CARTO, in particular, can be quite technically demanding and expensive.

 

Some patients don’t have a vein suitable for BRTO. In such cases, BATO (Balloon-occluded Antegrade Transvenous Obliteration) approaches the varices from the portal-vein side (inflow) or through the liver. Sometimes, it may even be combined with BRTO. For very complex portal hypertension cases, a team may combine varix-closing treatment with TIPS, which lowers portal pressure.

 

 

Vein anatomy, bleeding urgency, liver function and expertise tend to determine the use of these advanced procedures.

The core limitation of BRTO is that it treats the varices/shunt complex, but not the underlying cirrhosis or portal hypertension. Since it is a pressure-relieving operation, there is a chance that it can increase portal venous pressure. As a result, it can worsen oesophageal varices, portal hypertensive gastropathy or ectopic varices.

 

The benefits are many. It’s highly effective in controlling and eradicating gastric varices. According to some studies, rebleeding rates are much lower with BRTO, compared to TIPS (4.7% to 13.1%).

 

In cases where a large shunt is driving refractive hepatic encephalopathy, BRTO can lead to remarkable improvements.

 

Post-procedure encephalopathy risks tend to be lower than patients selected for TIPS, as BRTO does not create a new liver-bypassing shunt. This means, more blood passes through the liver and gets detoxified.

During or after the procedure, there might be bruising or bleeding at the catheter entry site, temporary pain, fever, nausea, an allergic reaction to contrast dye, or reduced renal function. Very rarely, the injected closing material or a clot can move beyond the intended veins.

 

As explained previously, the main concern with BRTO is that it closes a pressure-relieving shunt. This could solve one problem, while leading to another — pressure in the portal veins may increase and lead to new, and worsening ascites, oesophageal varices or bleeding from those veins. Blood clots in nearby veins or incomplete closure with recurrent bleeding are less common complications.

 

Close follow-ups with scans, blood tests and endoscopy helps identify these risks early on. Red flags to look out for are: severe abdominal pain, vomiting blood, black or tar-like stools, fainting, worsening breathlessness, fever or suddenly increasing abdominal swelling.

 

Recovery and Rehab

 

Most patients require monitored inpatient observation after BRTO. This stage of observation and care tends to focus on haemodynamic stability, pain/nausea control, access-site checks for wounds, blood counts, renal function tests, liver tests and surveillance for recurrent bleeding.

 

After discharge, exertion, heavy lifting and extremely physical activity is to be avoided, until the access site heals. In the case of Cirrhosis patients, nutrition management and avoiding alcohol is crucial. A deteriorating liver can lead to further problems.

 

Once the access site heals, short easy walks and gentle balance and flexibility work may be added. After medical clearance, light resistance training around the 30-40% capacity range may be resumed. Over time, a common long-term target is about 150 minutes of moderate activity per week. This amounts to 30 minutes, 5 times a week.

 

Patients with uncontrolled ascites, recent bleeding, severe weakness and encephalopathy/confusion should consider supervision while exercising. Dizziness can be a risk which could lead to physical injuries. Based on the patient’s profile, sometimes doctors suggest a cardiac/pulmonary rehab style individualized program. However, there is no standardized BRTO rehab protocol. It’s just about monitoring, watching for symptoms and easing into physical activity.